Missile and powerplant



J. J. LOVINGHAM ET AL 3,482,404

Dec. 9, 1969 MISSILE AND POWERPLANT l7 Sheets-Sheet 1 Filed Dec. 18, 1962 INVENTORS' JOS'PH J. lOV/A/GHA M HA ETMA/VN J. Klfi'f/EAE Dec.'9, 1969 J, J, LQVINGHAM ET AL 3,482,404

MISSILE AND POWERPLANT Filed Dec. 18, 1962 i I 17 Sheets-Sheet 2 II II V JET VECTOR CONTROL II II AFT DISPLACEMENT OFTHRUST VECTOR INCREASE IN THRUST [VECTOR MOMENT ARM fiz' [A INVENTORS JOSFPH J. LOV/NGHA M HARTMANN J. K/QCHER JZZ Dec. 9, 1969 J. J. LOYINGHAM ET AL MISSILE AND POWERPLANT 17 Sheets-Sheet Filed Dec. 18, 1962 INVENTORS Av NV hmOOm zorrqzzzmmh JOSfPH J. LOV/Nf/AM HARTMANA J. KAQOMWJE Dec. 9, 1969 L WNGHA'M ET AL 3,482,404

MISSILE AND POWERPLANT Filed Dec. 18, 1962 17 Sheets-Sheet 6 SHOCK FREE S URFACE ACORN COMBUSTION CHAMBER MACH LINE *w INVENTORS JOSEPH J. LOV/A/G/MM BY HA ETM/M/N J. K/IQCA/ERZZ' J. J. LOVINGHAM ET L 3,482,404

Dec. 9, 1969 MI S S ILE AND POWERPbANT 17 Sheets-Sheet '7 Filed Dec. 18, 1962 INVENTORS JOSEPH J. LOV/A/GHA M f/A/QTMAN/V J. K/QC/lf/ I as F&

Dec. 9, 1969 J J, mnN ET AL 3,482,404

MISSILE AND POWERPLANT Filed Dec.- 18, 1962 17 Sheets-Sheet 8 ACORN DEFLECTED SHOCK 1N VEN TORS JOSPH J. 1 OW/VGf/AM HAPTMAA/N J. K/QCHE? E Dec. 9, 1969 J. J- LOVINGHM ET AL 3,482,404

MIS S ILE AND POWERPLANT Filed Dec. 18, 1962 17 Sheets-Sheet 4(- THROAT( BASIC) 3Q /63- THROAT(THROTTLED) FREE SURFACE SHOCK 60- ACTUATING CYLRNDER ACORN comsusnon CHAMBER-36 59 ZQEJSQ MACH LINE T0 ACORN INVENTORS JOSEPH J. ZOV/A/GI /AM Y HAPfM/lN/V JK/RCHE/P H AGENT 17 Sheets-Sheet 1n 4.[-THROAT(BASIC) /63-THROAT(THROTTLED) Dec. 9, 1969 J. J. LOVINGHAM ET AL MISSILE AND POWERPLANT Filed Dec. 18, 1962 mm H mw M U D P 8 an mfi 3 A Mac 66 O mNA 6 SW0 VWVA m my L 9 JW 5 #4 Hm 7 M 3 JH w w 7 \\\4 lv /J ACORN DEFLECTED FREE SURFACE MACH LINE fizyc l/A ACORN COMBUSTION CHAMBER Dec. 9, 1969 J J, ovm ET AL 3,482,404

MISSILE AND POWERPLANT Filed Dec. 18, 1962 l? SheetsSheet 11 SHOCK FREE SURFACE ACORN comausnow CHAMBER-36 MACH L|NE\ INVENTORS JOSFPH J. L OV/NGHA M HAPTMAA/N J. K/fiCf/E'Qfl Dec. 9, 1969 ovm H ET AL 3,482,404

MI SS ILE AND POWERPLANT Filed Dec. 18, 1962 1'7 Sheets-Sheet 12 66 -CONTROL GAS PASSAGE Fly. 15 v F F m INVENTORS Dec. 9, 1969 ovm A ET AL 3,482,404

MISSILE AND POWERFLANT Filed Dec. 18, 1962 17 Sheets-Sheet 15 74- IGNITER 75-1NITIAT0R 80-UQUID INJECTOR ORIFICES 83 souo PROPELLANT GRAIN 78 so u l a 29 76 5% JOS L0 f7 [6 HA/ZTMA Mu J. Km CHE/Q 12" AGENT Dec. 9, 1969 J. J. LOVINGHAM ET AL 3,482,404

MISSILE AND POWERPLANT Filed Dec. 18, 1962 17 Sheets-Sheet 14 ACORN CHAMBER 57 CATALYST BED- 88 Fi m [9 INVENTORS JOSEPH J. LOV/A/H/IM HA ETMAN/V J. /(//?C/-/E/? H Dec. 9, 1969 J. J. LOVINGHAM ET AL 3,482,404

MISSILE AND POWERPLANT l7 Sheets-Sheet 15 Filed Dec. 18, 1962 TO SF INVENTORS JOSEPH J. LOW/VGHAM HART/MAW J. KAQCHEP H Dec. 9, 1969 J, LOVING-HAM ET AL 3,482,404

MISSILE m POWERPLANT 1'7 Sheets-Sheet 16 Filed D90. 18, 1962 zoEmol mwia 2253 hmOOm ZOFEmOQ mwqIl INVENTORS J0P// J. ZOW/VG/IAM United States Patent 3,482,404 MISSILE AND POWERPLANT Joseph J. Lovingham, Madison, and Hartmann J. Kircher III, Sparta, N.J., assignors to Thiokol Chemical Corporation, Bristol, Pa., a corporation of Delaware Filed Dec. 18, 1962, Ser. No. 247,443

Int. Cl. F02k 9/02 US. Cl. 60-259 10 Claims This invention relates generally to reaction motors and particularly to an improved rocket powerplant or missile having an improved construction and a novel type of thrust chamber.

Rocket powerplants of various types are well known in the art and most ofthese are characterized by at least several of a considerable number of disadvantages inherent in each of the various types. Among these disadvantages are: the use of separate thrust chambers for multistage operation; a lowered payload or fuel capacity due to the volume of the powerplant occupied by the thrust chamber; an inability to vary the thrust of the powerplant or to effect thrust vector control; the use of complicated control and/0r pressurizing systems resulting in added weight and air frame space requirements; an inability to effect packaging of the powerplant; an inability to effect a termination of thrust simply and accurately; and an excessive weight, length and/0r cost without resulting in a higher reliability.

Accordingly the main object of the present invention is to provide an improved, packaged, rocket powerplant having an engine with a novel type of thrust chamber and which will obviate the above and other disadvantages characterizing known prior art structures.

An important object of the present invention is to provide an improved rocket powerplant in which the volume normally occupied by the combustion chamber of the engine may be utilized for propellant loading to effect an increase in mass ratio for the missile.

Another important object of the present invention is to provide an improved rocket powerplant having a rocket engine embodying a novel thrust chamber hereinafter designated as an acorn thrust chamber which pro vides: a control of thrust level; an optimum nozzle expansion; a simple, high response, thrust vector control; eflicient packaging; and simple, accurate thrust termination.

A further important object of the present invention is to provide an improved rocket powerplant and missile which: has a rocket engine which uses a single combustion chamber for both boost and sustain thrust; uses a single, low temperature solid propellant gas generator for propellant feed, thrust vector control, roll control and venier velocity control; employs jettisonable booster tanks that are separated by a liquid fueled, shaped charge system that is inert until the engine ignites; and contains the payload, guidance, etc. within the tankage, and thus affords the advantages of lower weight, shorter length, lower cost, and higher reliability, over the conventional two stage approach.

A still further important object of the present invention is to provide an improved rocket powerplant of the type described which embodies a booster tank jettison system, a safety destruct system, and which may be armed when desired by the insertion of initiators for the two systems and for the solid pressurization grain of the gas generator.

Another important object of the present invention is to provide an improved rocket powerplant having a novel engine of the type described wherein thrust vectoring during boost operation is achieved by swiveling the acorn thrust chamber about a universal joint by mechanical means or by means of combustion gases bled through 3,482,464 Patented Dec. 9, 1969 the aft end of the chamber and controlled by the oblique shock technique.

A further important object of the present invention is to provide a fluid pressure balanced, universal joint pivot for the acorn thrust chamber of the engine so that only minimal forces are required to effect swiveling of the chamber during thrust vectoring.

A still further important object of the present invention is to provide novel means for effecting thrust vectoring of a rocket engine having a fixed acorn thrust chamber.

Another important object of the present invention is to provide a two-stage, packaged, liquid propellant, powerplant having a solid propellant pressurizing system embodying automatic valves operable upon termination of the first stage to shut off pressurizing gas flow to the first stage propellant tanks and admit it to the second stage tanks.

A further important object of the present invention is to provide a two stage, packaged, liquid propellant powerplant having a propellant flow control valve assembly initially operable by propellant pressure for first stage propellant flow, then operable by pressuring gases to second stage operation, and finally operable to shut down position by spring means.

A still further important object of the present invention is to provide a novel rocket engine having a thrust chamber of conical or acorn shape with an open base or forward end positioned adjacent a contoured deflecting surface with which the rim of the cone or acorn defines an expansion nozzle for the combustion gases which burn in the acorn.

Another important object of the present invention is to provide a missile in the form of an improved rocket powerplant which is the vehicle for a payload or warhead, and a guidance system, etc. mounted within the propellant tankage; employs jettisonable booster tanks; and is provided with a rocket engine having a single combustion chamber for both booster and sustain operational phases.

Other objects and advantages of the present invention will become apparent during the course of the following description.

In the drawings we have shown several embodiments of the invention. In these showings:

FIGURE 1 is a schematic view of the novel rocket powerplant and missile comprising the present invention;

FIGURE 1A is a similar fragmentary view showing the amplified thrust vector effect when the acorn thrust chamber is tilted;

FIGURE 2 is a schematic view to a reduced scale showing the several stages of operation of the invention;

FIGURE 3 is a schematic view of the preferred form of the novel rocket powerplant showing the propellant, pressurizing, and control connections;

FIGURE 4 is a fragmentary, central, longitudinal sectional view to an enlarged scale of the preferred form of the acorn thrust chamber and nozzle and the controls therefor;

FIGURE 5 is a fragmentary similar view thereof but taken at an angle turned with respect to FIGURE 4;

FIGURE 6 is a schematic, fragmentary, central longitudinal sectional view of a fixed acorn thrust chamber and nozzle as used with bipropellants;

FIGURE 7 is a similar view showing the acorn thrust chamber provided with one form of mechanical means for effecting thrust vector control;

FIGURE 8 is an aft end view of the vector control sectors of FIGURE 7;

FIGURE 9 is a view similar to FIGURE 7 showing a modified form of vector control means;

FIGURE 10 is a view similar to FIGURE 6' but showing the acorn thrust chamber and nozzle swivelly mounted by means of a ball joint pivot and another modification of mechanical means for effecting vector control by tilting the acorn;

FIGURE 11 is a view similar to FIGURE 6 but showing the acorn thrust chamber mounted for axial movement by fluid power means to vary the throat area and hence the thrust of the powerplant;

FIGURE 11A is a view similar to FIGURE 6 but showing the acorn chamber swivelly mounted to mechanically vary the thrust vector, and for axial movement;

FIGURE 12 is a view similar to FIGURE but showing the employment of aerodynamic actuation for thrust vector control, combustion gases being bled from a nozzle at the apex of the acorn rearwardly and subject to auxiliary moment producing control forces;

FIGURE 13 is a fragmentary sectional view to an enlarged scale of the acorn and its apex nozzle of FIGURE 12 showing the means for producing the auxiliary control forces;

FIGURE 14 is a transverse, sectional view thereof taken on the line 1414 of FIGURE 13;

FIGURE 15 is a fragmentary schematic view showing the axial nature of the flow through the apex nozzle in the absence of control fluid forces;

FIGURE 16 is a similar view showing the deflection of the apex nozzle flow under the influence of control fluid;

FIGURE 17 is a central, longitudinal sectional view to a decreased scale of another form of the acorn powerplant which uses a solid propellant;

FIGURE 18 is a similar view of another form of the acorn powerplant which is a hybrid using both liquid and solid propellants;

FIGURE 19 is a similar fragmentary view of another form of the acorn powerplant which uses a monopropellant and a catalyst bed;

FIGURE 20 is a transverse sectional detail view taken on the line 2020 of FIGURE 1;

FIGURE 21 is a similar view taken on the line 2121 of FIGURE 1;

FIGURE 22 is a similar view taken on the line 2222 of FIGURE 1;

FIGURE 23 is a greatly enlarged view of the dash line encircled portion of FIGURE 1;

FIGURE 24 is an enlarged view of the flow control valve assembly portion of the controls shown in FIG- URE 4; and

FIGURE 25 is a schematic view of the signaling circuits for effecting the proper sequential operational steps of the powerplant.

Referring to the drawings, the preferred form of the improved missile and powerplant which is designated as a whole by numeral 30, includes a sustain fuel tank SF, a sustain oxidizer tank SO, 2. gas generator chamber PG, and an abutting cylindrical chamber G containing guidance controls, etc., all being rigidly connected as an airframe designated as a whole by numeral 32.

A payload P which may be a warhead, instrumentation, and/or personnel capsule, guidance, etc., is releasably mounted on the forward end of the chamber G and enclosed by annular, jettisonable boost oxidizer and boost fuel tanks B0 and BF respectively which are rigidly connected to each other and to the airframe 32. The boost oxidizer and boost fuel tanks are automatically jettisoned upon conclusion of boost operation phase (FIGURE 2) by shaped charges set off by a control signal, as will be described. The rocket engine and its controls designated as a whole as J is mounted centrally in the aft end of the airframe as is conventional.

Throughout the specification the term engine refers to the combustion chamber including the exhaust nozzle, propellant injection means, etc. while the term powerplant refers to the missile as a whole including the engine, the tankage, conduits, controls, etc.

BASIC FORM OF ACORN ROCKET ENGINE A basic form of the novel rocket engine of the present invention is disclosed in FIGURE 6 in which numerals 33 and 34 designate pressurized oxidizer and fuel tanks of the powerplant respectively, the rear wall 35 of the latter being contoured in shape, and in this particular embodiment, substantially hemispherical. Oxidizer and fuel are delivered to the conical or acorn thrust chamber 36 by concentric manifolds 37, 38 on which it is rigidly mounted. The rim of its large open end 40 is spaced from but adjacent the concave surface of the aft wall 35 of the fuel tank 34 so as to define an annular exhaust passage or nozzle throat 41 therewith.

The fuel in passing to the injection orifices 42 of the combustion and thrust chamber is directed along the rear hemispherical wall 35 by a conforming baffle 43 so as to regeneratively cool this exhaust gas deflecting surface. Similarly, oxidizer and fuel regeneratively cool the acorn thrust chamber 36 by means of a compartmented coolant jacket 44 before separately reaching the injection orifices 42. The fuel and oxidizer, being hypergolic, require no ignition and mix and burn in the thrust chamber, the gases passing around the open end 40 through the annular nozzle throat 41 and back along the deflecting wall 35, expanding and providing thrust.

It is to be noted that the arrangement just described enables the volume of the missile normally occupied by the combustion chamber to be available for propellant loading, thus effecting an increase in mass ratio for the missile. The use of the aft tank head or wall 35 for the deflection portion of the nozzle also increases the structural efficiency of the airframe so that the tank head serves a dual purpose.

BASIC ACORN ENGINE WITH MECHANICAL THRUST VECTOR CONTROL The basic acorn engine I of FIGURE 6 is readily modified for thrust vector control with mechanical actuating means as shown schematically and in section in FIG- URES 79 inclusive. The aft fuel tank wall 35 is modified to receive a ring 45 whose aft face is flush, i.e. providing uniform peripheral distribution of throat area, with the surface of the deflecting wall 35 except during those periods when a thrust vector direction other than axial of the motor is desired.

The ring 45 comprises three equal, arcuate sectors 46 to each of which one or more fluid pressure, extensible cylinders 47 are pivotally connected by V-shaped legs 48 at one end and to the central propellant conduit 49 at their other ends. The sectors 46 move in guides 50 to prevent their cocking which is also prevented by the V-shape d legs 48.

When thrust vector control is desired, fluid pressure is introduced into one or more of the cylinders 47 to move one or more of the sectors 46 into the throat area 41 to vary it and cause local disturbance to effect the vector control. Similar control is effected by the means disclosed in FIGURE 9 which differs from FIGURES 7 and 8 only in that a single complete ring 53 is used instead of the sectors 46.

It will be appreciated that the arrangements of FIG- URES 79 inclusive embodies a number of advantages in thrust vector control in that pivoting of the acorn is not required so that there is no resultant axial load which must be coped with, nor need for pivotal propellant lines. Moreover, the central conduit 49 permits eflicient hydraulic actuation design.

As indicated above, the requirement for thrust vector control normally requires that the combustion chamber of a rocket engine be swiveled or gimballed, or, as illustrated, that auxiliary devices be used to effect jet deflection. The acorn thrust chamber, as shown in FIGURE 10, embodies another new and unique mechanical way of obtaining thrust vector control by providing the concentric fuel and oxidizer manifolds 37, 38 which support gravity enables the minimizing of the effect of inertial loads during its maneuvering to also enable a minimization of actuating force. As shown in dotted lines in FIG- URE 10, the acorn 36 is deflected by one of three fluid actuators 56 spaced 120 apart so that the proportion of thrust generated in the upper portion is appreciably greater than that in the lower portion. A clockwise turning (yawing) movement is therefore generated due to the asymmetric thrust generation.

BASIC ACORN ENGINE WITH THRUST CONTROL As illustrated in FIGURE 11, the thrust of the engine J may be readily varied by mounting the acorn 36 on extensible, concentric manifolds 57 which slide in a suitably sealed housing 58 and are connected to a piston 59 in a fluid pressure actuating cylinder 60. Actuation, as demanded by a control system, will linearly translate the acorn chamber 36 along the fore and aft axis .to vary the throat area 41 and throttle it as shown at 63 and thus change the thrust of the engine. As the throat area 41 is decreased the expansion area ratio increases which is desirable for high performance of the sustainer at extreme altitudes.

BASIC ACORN ENGINE WITH THRUST AND MECHANICAL VECTOR CONTROL A combination of mechanically actuated thrust vector control and throttling or thrust control is disclosed in FIGURE 11A, which as indicated by similar numerals for similar parts, is a combination of the disclosures of FIGURES and 11. As is apparent, the acorn thrust chamber 36 is mounted on the manifolds ball joint pivot 54 which receives propellants from the slidable, extensible, concentric manifold 57. Thus, the acorn 36 is free to pivot about the pivot point and to move fore and aft within the limits of the extensible manifolds.

It is to be noted that the same combination of pivoting and axial movement is disclosed in the preferred form of the invention (shown in detail in FIGURE 4), the distinction being that thrust vector control is effected aerodynamically.

ACORN ENGINE WITH AERODYNAMIC THRUST VECTOR CONTROL An acorn thrust chamber which employs aerodynamic actuation for thrust vector control is disclosed in FIG- URES 12-16 inclusive. The acorn 36 as shown therein includes a compound exhaust plug nozzle 64 at its apex through which combustion gases are bled rearwardly around the partially internally expanded plug 65 Which has a plurality of equally angularly spaced control gas passages 66 each individually controlled by a valve 67. As suggested in FIGURE 13, the acorn 36 may include an outer manifold 68 for the injection of a diluent through apertures 69 for the purpose of cooling the hot gas passing through nozzle 64.

With the arrangement just described, it is possible to induce varied and eccentric forces at the apex or aft end of the acorn 36 which produce a moment about the ball joint 54 to cause the acorn to rotate or pivot to the desired position for asymmetric thrust generation. As seen in FIG- URES 12 and particularly 15, the thrust producing fluid (combustion gases bled rearwardly through the nozzle 64) normally flows about the central plug 65 in isentropic flow and the thrust F produced is axial or along the central line of the plug.

When an asymmetric thrust force is desired, a secondary mass in the form of control fluid (i.e. gas or liquid such as inert control gas, combustion gas liquid propellant or other liquid) is injected through one of the control passages 66 as shown in FIGURE 16. The addition of this secondary mass forces a local portion of the bled exhaust gases to be locally deflected away from the central plug 65. The combustion gases bled through the acorn apex now take an overall slightly different direction of flow. As a result, a local thrust component other than axial is produced and a force tending to rotate the nozzle about the ball joint 54 is produced.

The losses associated with this vector control system are minimized since only small actuation and control forces are needed.

SOLID PROPELLANT ACORN ENGINE The acorn engine may employ a solid propellant (FIG- URE 17) which is molded into a monolithic type acorn thrust chamber 70 coated with an ablative material and mounted on a central supporting manifold 73 extending from a hemispherical deflecting surface 71 and provided with an igniter 74 and an initiator 75. The nozzle or deflecting surface 71 is also lined with an ablative material 76.

It will be apparent that the throttling and thrust vector control means of FIGURES 10 and 11 as well as the vector control mechanism of FIGURES 12-16 inclusive are applicable to the solid propellant form shown. From a practical aspect, this solid propellant form will be very useful for low or moderate total impulse levels at high expansion area ratios.

HYBRID ACORN ENGINE As shown in FIGURE 18, a liquid propellant may be fed through the supporting manifold 73 from a tank 77 which is pressurized by solid grain 78 ignitable by a squib 79. The liquid propellant is injected into the solid propellant grain in the acorn thrust chamber 70 through orifices 80 and the quantity of liquid propellant injected is controlled by a throttling valve 83 to further control the performance of the unit.

It will be apparent that the throttling and thrust vector control means of FIGURES 10 and 11 as well as the vector control mechanism of FIGURES 12-16 inclusive are applicable to this hybrid acorn engine.

MONOPROPELLANT ACORN ENGINE A further embodiment of the acorn engine is disclosed in FIGURE 19 wherein a liquid monopropellant is introduced into the acorn chamber supporting manifold 84 from a tank 85 and injected through orifices 86 at the aft end of the acorn thrust (decomposition) chamber 87 into and through a catalyst bed 88. Upon decomposition, the gases pass through the nozzle throat 89 and expand along the deflecting surface 90' of the tank 85 and around the acorn chamber 87.

This form of the acorn engine I exploits the reverse flow of the combustion gases and the acceleration of the powerplant and missile to improve the decomposition and/or combustion of the monopropellant. The acceleration of the powerplant will result in keeping the liquid monopropellant within the catalyst bed 88 until it throughly decomposes and develops suflicient pressure to force the gaseous decomposition products through the nozzle throat 89.

As a result, a smaller catalyst bed is required and there is less danger of flooding. This in turn effects more eflicient decomposition and gives inherent geometry and pressure drop advantages in that the largest flow area is at the position corresponding to the highest gas temperature and highest gas specific volume. Also, the throttling and thrust vector control means of FIGURES l0 and 11 are applicable to this form of engine. 

1. A ROCKET POWERPLANT COMPRISING, IN COMBINATION, A COMBUSTION CHAMBER HAVING AN EXHAUST NOZZLE, A PROPELLANT TANK INCLUDING PROPELLANT COMMUNICATING WITH SAID CHAMBER, A PRESSURE GAS GENERATOR, AND CONTROL MEANS, ALL BEING RIGIDLY SECURED TOGETHER TO DEFINE AN AIRFRAME, A SECOND PROPELLANT TANK SECURED TO SAID AIRFRAME AND COMMUNICATING WITH SAID CHAMBER, AND VALVE MEANS CONNECTED TO SAID GENERATOR AND EACH OF SAID TANKS TO SUCCESSIVELY ADMIT PRESSURE GAS TO SAID SECOND AND FIRST-MENTIONED TANKS TO DELIVER THE PROPELLANT TO SAID CHAMBER. 